This paper is concerned with the computational results of two-dimensional axisymmetric rigid and elastic wall formulation. In this paper, steady flow in a stenotic vessel is simulated and compared to available numeric...This paper is concerned with the computational results of two-dimensional axisymmetric rigid and elastic wall formulation. In this paper, steady flow in a stenotic vessel is simulated and compared to available numerical data with COMSOL Multiphysics software. Numerical results for a 2D axisymmetric vessel of 45% area reduction indicate that as the area is reduced with the decreasing of cross-section, the maximum axial velocity at post stenotic decreases until the end of the artery but the radial velocity increases upto 4 mm from the stenosis throat and then decreases. Overall, comparison is carried out on hemodynamics for elastic and rigid wall of steady flow. Our investigated findings may enable risk factor for patients with attacked cardiovascular diseases and can play an important role to detect a solution to such kinds of diseases.展开更多
Unsteady currents fluids flowing through a baffle with holes found in a mobile storage tank are complex to analyze. This study aims to evaluate the effects of fluid structure interactions (FSI) on baffles in tanks car...Unsteady currents fluids flowing through a baffle with holes found in a mobile storage tank are complex to analyze. This study aims to evaluate the effects of fluid structure interactions (FSI) on baffles in tanks carried on mobile trucks that, more often than not, experience sloshing phenomenon engulfed by turbulences behaviors with respect to different motions of the truck. Mindful of the different types of baffles that are used in the tanks to limit sloshing wave activities and improve safety by allowing fluid to pass through carefully designed holes that are also placed in a specific pattern, the fluid structure interaction around a baffle with a hole is evaluated here through computing. Passing through the solver in COMSOL, an equivalent design tank and baffle with a hole is discretized to point form such that the fluid flowing through each point is evaluated and interpreted on a point graph generated with respect to each point located on the tank or baffle hole. The result obtained not only shows the effects of FSI as a function of turbulence kinetic energy per individual point but also the contour pressure field and velocity magnitude of the entire system.展开更多
针对液压滑阀在中高压系统中,粘性加热使油流温升显著,阀芯受热膨胀,发生磨损甚至卡紧的现象,该文建立了液压滑阀的计算机流体力学(Computational Fluid Dynamics,CFD)三维模型和稳态传热有限元模型(Finite Element Analysis,FEA),利用...针对液压滑阀在中高压系统中,粘性加热使油流温升显著,阀芯受热膨胀,发生磨损甚至卡紧的现象,该文建立了液压滑阀的计算机流体力学(Computational Fluid Dynamics,CFD)三维模型和稳态传热有限元模型(Finite Element Analysis,FEA),利用流固耦合(Fluid-Solid Interaction,FSI)计算了阀芯在不同开口度下的速度、阀芯温度和阀芯热变形量,分析阀芯在不同开口度下的最高温度和最大变形量的变化趋势,为液压滑阀的设计提供一定的参考意义。展开更多
The Hydrodynamic Ram(HRAM)effect occurs when a high kinetic energy projectile penetrates a fluid filled area,e.g.,a liquid filled tank.The projectile transfers its momentum and kinetic energy to the fluid,what causes ...The Hydrodynamic Ram(HRAM)effect occurs when a high kinetic energy projectile penetrates a fluid filled area,e.g.,a liquid filled tank.The projectile transfers its momentum and kinetic energy to the fluid,what causes a sudden,local pressure rise,further expanding as primary shock wave in the fluid and developing a cavity.It is possible that the entire tank ruptures due to the loads transferred through the fluid to its surrounding structure.In the past decades,additionally to experimental investigations,HRAM has been studied using various computational approaches particularly focusing on the description of the Fluid-Structure Interaction(FSI).This article reviews the published experimental,analytical and numerical results and delivers a chronological overview since the end of World War II.Furthermore,HRAM mitigation measures are highlighted,which have been developed with the experimental,analytical and numerical toolboxes matured over the past 80 years.展开更多
文摘This paper is concerned with the computational results of two-dimensional axisymmetric rigid and elastic wall formulation. In this paper, steady flow in a stenotic vessel is simulated and compared to available numerical data with COMSOL Multiphysics software. Numerical results for a 2D axisymmetric vessel of 45% area reduction indicate that as the area is reduced with the decreasing of cross-section, the maximum axial velocity at post stenotic decreases until the end of the artery but the radial velocity increases upto 4 mm from the stenosis throat and then decreases. Overall, comparison is carried out on hemodynamics for elastic and rigid wall of steady flow. Our investigated findings may enable risk factor for patients with attacked cardiovascular diseases and can play an important role to detect a solution to such kinds of diseases.
文摘Unsteady currents fluids flowing through a baffle with holes found in a mobile storage tank are complex to analyze. This study aims to evaluate the effects of fluid structure interactions (FSI) on baffles in tanks carried on mobile trucks that, more often than not, experience sloshing phenomenon engulfed by turbulences behaviors with respect to different motions of the truck. Mindful of the different types of baffles that are used in the tanks to limit sloshing wave activities and improve safety by allowing fluid to pass through carefully designed holes that are also placed in a specific pattern, the fluid structure interaction around a baffle with a hole is evaluated here through computing. Passing through the solver in COMSOL, an equivalent design tank and baffle with a hole is discretized to point form such that the fluid flowing through each point is evaluated and interpreted on a point graph generated with respect to each point located on the tank or baffle hole. The result obtained not only shows the effects of FSI as a function of turbulence kinetic energy per individual point but also the contour pressure field and velocity magnitude of the entire system.
文摘The Hydrodynamic Ram(HRAM)effect occurs when a high kinetic energy projectile penetrates a fluid filled area,e.g.,a liquid filled tank.The projectile transfers its momentum and kinetic energy to the fluid,what causes a sudden,local pressure rise,further expanding as primary shock wave in the fluid and developing a cavity.It is possible that the entire tank ruptures due to the loads transferred through the fluid to its surrounding structure.In the past decades,additionally to experimental investigations,HRAM has been studied using various computational approaches particularly focusing on the description of the Fluid-Structure Interaction(FSI).This article reviews the published experimental,analytical and numerical results and delivers a chronological overview since the end of World War II.Furthermore,HRAM mitigation measures are highlighted,which have been developed with the experimental,analytical and numerical toolboxes matured over the past 80 years.
